Rotary vane vacuum pump or compressor



March 16, 1943. A. SO'BEK 1 2,

ROTARY VANE VACUUM PUMP OR COMPRESSOR Sheets-Sheetl March 16, 1943. A. SOBEK ROTARY VANE VACUUM PUMP OR COMPRESSOR Filed May 9, 1959 2 Sheets-Sheet 2 Patented Mar. 16, 1943 ao'raav VANE vacuum PUMP on comnassoa Andr Sobek, Paris, France; vested in the Alien Property Application May 9, 1939, Serial No. 272,666

In Luxemburg February 22, 1939 2 Claims. (Cl- 230153) The present invention relates to rotary vane vacuum pump or compressor.

A first improvement lies in the fact that the pump body is provided with an internal cylindrical surface the directrix of which is formed by a conchoid of a circle, along which surface slide the edges of two vanes which cross each other perpendicularly on the polar axis of the directrix, about which axis they rotate under the action of a rotary driving member relatively to which they are capable of sliding, and there exists coupling means which connects said two vanes to each other in order to form a floating self balanced system.

This arrangement enables, the centrifugal forces which are exerted on the two vanes to be compensated by each other. owing to the fact carries nipples 2 and the internal surface of which is preferably cylindrical. Inside said casing I is lodged a hollow inner body 4 of smaller diameter than the inner diameter of said casing space 6 is thus provided between the outer casing l and the inner body 4 over the greater part of their length. The internal surface of the hollow body 4 is formed by a cylindrical surface the directrix of.which is formed by a conchoid.

of the circle C of which the centre is O, the pole .of the conchoid being at P (Fig. 5). Said body is closed at its two opposite ends by plates l which are fixed at the end of the inner body 4 I and-which are each provided with a bearing, the

that said two centrifugal forces are at all times equal and opposite, provided that said two vanes have the same mass and that their centre of gravity is located at their geometrical centre,

" the suction pipe and with the inside of the cylinder so that the gaseous fluid passes through it before its introduction into the pump body; the

heating of the pump body is thus attenuated.

Other improvements that may further be provided .in an improved rotary vane-machine according to the present invention will become apparent during the ensuing description.

In said drawings: Fig. l is a longitudinal section of a construction of a conchoid pump; Fig. 2 is a corresponding transverse section. Figs. 3 and 4 are respectively general perspective views of the two vanes shown separately, and of the driving member for the vanes, which is shown partly broken away.

Fig. 5 is a diagram explaining the operation. In the exemplary embodiment shown the ma; chine comprises a hollow outer casing l which axis of which passes through the pole P and in which is lodged a ball bearing 8. Said'ball bearings'8 support the axial journals 9 of ahollow cylindrical driving member It, the outer surface of which is tangential to the. conchoid surface. Said driving member ID is composed of four identical parts (Fig. 4) each formed by a cylindrical ring portion H which extends over a little less than one quarter of a circle, the length-of which is equal to the distance between the plates 1, and which terminates at the end by an end i2 carrying on the outside a circular rib l3. At each end the four parts II are held assembled other sides on the conchoid surface along two opposite generatrices. Said two vanes l6 are suitably hollowed. in order to intercross each other inside the driving member and .to move therein withoutltouching' each other; for this purpose (Fig. 3) one of the vanes is H-shaped and the other is provided with a central recess of rectangular shape. On each vane'and inits axis of symmetry XX parallelto its axis of rotation are fixed two small opposite journals I1 and the journals of one vane are'connected to the two journals of the other by two connecting rods N! (Fig. 3).. Furthermore. the centre of gravity of each vane is located at its geometrical centre. and said two vanes are so constructed as rack '(not shown) to be of exactly the same weight. A floating system is thus formed.

On the other hand, holes i8 through the wall of the inner body 4 in its part adjacent the generatrix of contact, place the annular chamber 6 in communication with the inside of said body and said annular chamber 6 isintercepted by a shoulder 20. One of the nipples 2 opens directly into said annular chamber whereas the other is extended by a conduit 2| which passes through the chamber 6 and opens inside the inner body.

When the driving member i is rotated, the vanes l8 slide in the slits but the middle gig: of each of them remains on the generating circle of the conchoid (Fig. and as the two vanes always pass through the fixed pole P and remain perpendicular to each other, these two middles are located at the ends of a diameter of the circle C. As the centres of gravity of the two vanes are located by construction at the centres or and g: of said vanes, it will be seen that the centrifugal forces f1 and fa that are exerted respectively on said two vanes are constantly equal and opposite; the floating system is thus selfbalanced owing to the connecting of or to a: by-

the connecting rod is, thereby considerably reducing friction between the vanes and the driving member and also between the vanes and the conchoid surface.

In other respects the machine operates like known conchoid pumps. Furthermore the air that penetrates through the suction nipple 2 has to circulate substantially from one end to the other of the annular chamber Gbefore penetrating into the inner body 4 throu h the holes l8 and thus acts to cool said inner body.

, The pump is furthermore provided with a lubricating device formed by a micro-regulator of the type described in the patent application fi ed on this same day. in the name of the same inventor, entitled Differential pump. In the particular application that is made herein, said micro-regulatoris carried by one of the plates I. It comprises a part 22 fitted in a radial hole of .the wall of the bearing carried by said plate:

sa d part 22 is itself provided with two holes 23 which run right through same and the axes of By creating a lag differing very slightly from 180 in the movements of the two pistons 24, a very small discharge rate will be produced; said lag is obtained in this case by slightly rotating the part 22 on its axis in its housing in such a manner that the points of contact of the heads 25 with the eccentric bearing surfaces of the sleeve 21 are not in the same plane as the axis of rotation of the Journal 9, said part 22 being locked in position only by the pressure of the plug 29 on a shoulder 38 of said part; the discharge rate of the micro-regulator is thus adjusted by varying said lag when the pump is stopped.

Of course, the invention is in no way limited to the constructional details illustrated and described which have only been given by way of example. Thus, inparticular the lubricator may be subjected to all the modifications provided in the aforesaid patent application.

What I claim is:

1. In a rotary vane pump or compressor including a casing providing a cylinder the directrix of which is formed by a conchoid of a circle, a rotatable vane arrangement provided within said cylinder, and comprising two vanes, each vane beingdiametrically arranged in said cylinder and cut away at their central portion so as to clear each others paths of movements and coupling means connecting said vanes'together, said coupling means, being formed by iournaling means mounting each of said vanes for rotation coaxially with its middle line and connecting means between said iournaling means maintaining said lines at a distance equal to the diameter of said circle, and a driving member rotating about an axis passing through the pole of said conchoid, said member being provided with four equally spaced slots for diametrically guiding said vanes, said vane arrangement forming a self-balanced floating unit, 1. e., having connection with the casing solely through the medium of said slotted driving member and thereby having freedom of movement within the casing transversely of the-rotary axis, said two vanes having the same weight and their centres of gravity at the intersection of their longitudinal middle lines with a single plane perpenwhich are perpendicular to the ams of the bearing. In each of said holes can move a rod 24 which forms a piston in this cylinder and extends outside the cylinder towardsthe axis of the hearing; this projecting part carries a head 25 which acts as a rest for a spring 26 which is interposed between said head and the part 22: said spring presses the head 25 against an eccentric bearing surface of a sleeve 21 fixed on the journal 9. The two eccentric bearing surfaces of said sleeve 21 are opposite each other. At their upper part. the cylinders 23 open into a small chamber 28 formed between the part 22 and a plug 28 screwed on top of said part in a hole of the bearing in which it is lodged.

Radial holes 3|, 82 through the wall of the cylinders 23, at a point' located at mid-stroke of a delivery pipe 34 which leads to a distributing Said rack is -formedby a hole that is bored longitudinally in the wall of the inner body 4 and tiny holes perpendicular to said wall place said hole in communication withthe inside of said body or with the annular chamber 8. i

dicular therewith.

2. In a rotary vane pumpor compressor including a casing providing a cylinder the directrix of which is formed by a conchoid of a circle, a rotatable vane arrangement provided within said cylinder and comprising two vanes. each vane being diametrically arranged in said cylinder and cut away at their central portion so as to clear each other's paths of movements and coupling means connecting said vanes together, said cpupling means being formed by iournaling means mounting each of said vanes for rotation coaxially with its middle line and connecting means between said journallng means maintaining said lines at a distance equal to the diameter of said circle. and a driving member rotating about an axis passing through the pole of said conchoid, said member being provided with four equally spaced slots for diametrally guiding said vanes. said coupling means consisting in two connecting rods and two pieces secured to each of said vanes and journaled on the ends of each connecting rod.

ANDRE SOBEK. 

